Say I have this code in Java: ``` interface Foo&l...

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[arekolek]

Say I have this code in Java:

interface Foo<T> {}

class JavaStringFoo implements Foo<String> {}

class JavaStringListFoo implements Foo<List<String>> {}

class Spam {
    Foo<String> one() {
        return new JavaStringFoo();
    }

    Foo<String> two() {
        return new KotlinStringFoo();
    }

    Foo<List<String>> three() {
        return new JavaStringListFoo();
    }

    Foo<List<String>> four() {
        return new KotlinStringListFoo();
    }
}

and this code in Kotlin:

class KotlinStringFoo : Foo<String>

class KotlinStringListFoo : Foo<List<String>>

I’d think KotlinStringFoo code is equivalent to JavaStringFoo and KotlinStringListFoo to JavaStringListFoo.

But I get this error in `four()`:

incompatible types: KotlinStringListFoo cannot be converted to Foo<List<String>>

This is while other three functions compile just fine. What’s up with that? How do I fix it?